Occupational exposure to ethylene oxide: effects and control

Ethylene oxide (EO) is widely used in the health care industry as a gas sterilant for medical products that cannot withstand the high temperature and humidity associated with conventional steam sterilization. As a consequence, approximately 100,000 health care workers are exposed to residual EO each year. The acute toxicity of exposure to EO has been well documented, and recent concern about the mutagenic potential of occupational exposure to EO has resulted in an effort to further reduce workplace exposure levels to EO. The Environmental Protection Agency has issued a rebuttal presumption against registration of EO as a pesticide and the American Conference of Governmental Industrial Hygienists (ACGIH) has proposed a sharp reduction in the threshold limit value permitted for EO. Recognizing the need for environmental health personnel to become more familiar with this workplace hazard, it is appropriate to briefly review the toxic effects of acute and chronic exposure to EO residuals. The authors describe a gas sterilization system successfully utilized at the U.S. Public Health Service Hospital in New Orleans, La., which has demonstrated exposure concentrations well below the EO threshold limit value recently proposed by the ACGIH, while preserving the principal goal of assuring the sterility of reusable medical products which cannot be subjected to steam sterilization.